Got worse, got him to the vet, got antibiotic pills, couldn't get them down him, got him to take them in his food. So he got better. I had him neutered and watch him pretty closely now because there's a couple strays I feed outside, and they have standoffs but no fighting.
I guess I wouldn't want to take a stray cat to those weekend ER's (I've done that with a couple of mine) but if it's still there tomorrow or keep it in the garage or something, take it to a cheaper vet. One of my last trips to the vet was to the cheapest one where you wait your turn. Somebody brought a little dog in that had gotten in a big dog's yard. The little one got back under the fence, and the man was holding it in a blanket. The dog got very quiet. My turn was and the vet came out and I said you'd better take that little dog.
She did, shut the door (usually didn't), got very quiet in there. Pretty soon he came out with a dead dog in a box. The vet came out crying. Internal injuries. It was awful to see. Guy leaves, pretty soon wife somes and starts yelling at the vet. Said that dog was alert before. I don't know if delay in treatment would have made a difference. I don't think there was much that could be done for the little thing.
Apart from scratches that could get infected and spread through his body your dog should be fine. Unusual for the cat to hang around though.
Sad. Just doing what critters do. I've seen a dog take out a cat with one chomp. Your dog must be small or nice not to do the same, claws or no claws.
Neighbor was a chiro, not a vet. They get lots of meds now though.